https://gastatic.com/blog/wp-content...te-chamber.jpg
Backplate will not effect your extractor issue according to our armored. He said the extractor could be damaged or bent or warn so it’s not a back of slide functioning issue at all. Check you springs and slide action and see if that isn’t it if the extractor is looking normal. Also make sure your ejector is proper. That might also be the cause. Easy to bend that little finger if not careful.
You don’t lube up in there do you?